Lower trading fees and other challenges could be a drag on large banks’ first quarter earnings, and while Jefferies analyst Ken Usdin is still bullish on the sector in the long-term, his EPS estimates are below consensus across the board and he thinks that investors are simply bracing for a disappointing 1Q14. “With a few weeks left in 1Q14, the EPS set-up for Bank of America Corp (NYSE:BAC), Citigroup Inc (NYSE:C), and JPMorgan Chase & Co. (NYSE:JPM) looks fairly challenging,” writes Usdin in a March 17 report. He estimates that trading fees are down as much as 20% from last…